The widely watched Fortune 500 list, released Sunday, showed that the world's largest listed oil company regained the top spot, raking in $442.9 billion of revenue in 2008, despite the decline of energy prices late last year.

Exxon also was the most profitable, earning $45.2 billion last year.

That performance displaced Bentonville, Arkansas-based Wal-Mart, which fell to runner-up after topping the list six of the past seven years. The retailer's revenue climbed 7 percent to $405.6 billion as recession-weary consumers tried to stretch their dollar.

In what was one of the worst years ever for stock markets, most companies saw revenue and earnings tumble. Overall, earnings of the Fortune 500 fell 85 percent to $99 billion last year. That, the magazine said, was the biggest one-year drop since it began compiling its list 55 years ago.

Energy companies, buoyed by soaring prices earlier in 2008, dominated the top ranks. Chevron Corp again came in third at $263.2 billion in revenue, up 25 percent, while ConocoPhillips climbed one notch to fourth with $230.8 billion of revenue.

General Electric Co , the industrial conglomerate weighed down by its financial arm's woes, still managed to rise one slot to fifth place.

As expected, money-losing financial services companies were the hardest hit last year. Citigroup Inc and Bank of America Corp fell out of the top 10, while Lehman Brothers, Washington Mutual and Wachovia Corp were among 38 companies dropping off the list completely.